Pulmonary stenosis is a congenital condition characterized by a narrowed pulmonary valve, causing the right ventricle to work harder, which can lead to symptoms like shortness of breath, fatigue, and cyanosis. Diagnosis involves auscultation, ECG, chest X-ray, and echocardiography, while treatment may include medical management, balloon valvuloplasty, or surgical options such as valve repair or replacement. Long-term management also requires monitoring for potential complications like infective endocarditis and managing cardiac output.